Systems and methods for charging an electric vehicle at a charging station

ABSTRACT

Systems and methods for charging an electric bus having a charging interface on its roof may include determining that an approaching bus is supposed to be charged at the charging station, lowering the charging head of the charging station to land on the roof of the bus, and moving the bus with the charge head on its roof to engage the charging head with the charging interface.

CROSS-REFERENCE

This application is a continuation application of U.S. application Ser.No. 13/643,541, filed Apr. 11, 2013, which is a National StageApplication of PCT/US2011/033915, filed Apr. 26, 2011, which claims thebenefit of U.S. Provisional Application No. 61/328,152, filed Apr. 26,2010. All of these applications are incorporated herein by reference intheir entireties.

BACKGROUND OF THE INVENTION

Heavy duty battery electric vehicles can require relatively frequentcharging to operate in normal service. Frequent charging atpredetermined charging station locations enables energy storage systemsto be sized with more certainty leading to reduce size, mass, and costof systems. That required frequency of charging means that manualconnection, such as physically plugging the vehicle in, to a charger isnot acceptable. Traditionally, manually connecting the vehicle requiresthe driver to park and then carry high voltage cables to plug in thevehicle. In a transit center distances to charging station equipmentcould be quite far from the bus leading to long lengths of heavy gagehigh voltage cable to reach the vehicle. Not only is this a distraction,it is not typical job task for drivers.

Therefore, a need exists for improved systems and methods for connectingan electric vehicle to a charging station. A further need exists forsystems and methods that provide a control strategy for automaticallyproviding such a connection and for subsequent charging of on-boardvehicle batteries.

SUMMARY OF THE INVENTION

The invention provides systems and methods for connecting an electric orhybrid electric vehicle to a charging station. The invention furtherprovides a control strategy for subsequent charging of on-boardbatteries. Various aspects of the invention described herein may beapplied to any of the particular applications set forth below or for anyother types of vehicles. The invention may be applied as a standalonesystem or method, or as part of an integrated transportation system,such as a bus system or other public transportation system. It shall beunderstood that different aspects of the invention can be appreciatedindividually, collectively, or in combination with each other.

In accordance with some aspects of the invention, absolute reliabilityand repeatability of the docking and charging process may be desired toensure continued operation. Due to the relatively harsh environment inwhich heavy duty vehicles operate, both the docking and battery chargingprocess itself may preferably be capable of handling a wide range ofsystem variability and conditions.

Some specific specifications that may be desirable may include thefollowing. Charging would preferably be performed on route to preventhaving to remove vehicle from service and drive to a special chargingstation, thereby reducing duty cycle. On route charging stationpreferably allows different, non battery electric vehicles to passthrough the station while correctly identifying when battery electricvehicles are in the terminal and require changing. For example, acompressed natural gas (CNG) or diesel powered vehicle may be allowed touse the same terminal as the battery electric vehicle. This means thedocking and charging equipment preferably remains unobtrusive untilrequired for use.

A vehicle's approach and dock with a charger is preferably safe,reliable and repeatable. A vehicle connection process may advantageouslyhave reduced or minimal driver interaction and limited change to driverbehavior.

An aspect of the invention may be to automate all or nearly all of theentire charging process for an electric vehicle. The vehicle may connect(dock) automatically with the charge station and the battery chargeprocess may take place automatically. This automated process ensures aproper charge every time and may allow for continuous, efficientoperation of the vehicle.

Other goals and advantages of the invention will be further appreciatedand understood when considered in conjunction with the followingdescription and accompanying drawings. While the following descriptionmay contain specific details describing particular embodiments of theinvention, this should not be construed as limitations to the scope ofthe invention but rather as an exemplification of preferableembodiments. For each aspect of the invention, many variations arepossible as suggested herein that are known to those of ordinary skillin the art. A variety of changes and modifications can be made withinthe scope of the invention without departing from the spirit thereof.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIG. 1 shows an example of a vehicle approaching a charging station.

FIG. 2 shows an example of a vehicle engaged with a charging station.

FIG. 3 shows an example of a charging connection of a charging station.

FIG. 4 provides a high level depiction of an automated charging method.

FIG. 5 provides a depiction of an automated charging method inaccordance with an embodiment of the invention.

FIG. 6A-F provides a block diagram for a docking and charging procedureas provided in an embodiment of the invention.

FIG. 7A-G provides a table describing the steps for an automatic dockingand charging procedure.

DETAILED DESCRIPTION OF THE INVENTION

While preferable embodiments of the invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the invention. It should be understoodthat various alternatives to the embodiments of the invention describedherein may be employed in practicing the invention.

The invention provides for systems and methods for connecting anelectric vehicle to a charging station. The invention further comprisessystems and methods for charging the electric vehicle at the chargingstation. One aspect of the invention provides for automated connectionbetween the vehicle and the charging station for charging of on-boardvehicle batteries. The charging station may be used to transfer power toany electric vehicle, hybrid electric vehicle, or any other vehicle thatmay include a propulsion power source, such as a battery,ultracapacitor, or any other energy storage system. In some embodiments,an electrically powered vehicle may be a heavy duty vehicle, such as abus or truck.

For example, electrical vehicles powered by the system may include atransit bus, a school bus, a delivery van, a shuttle bus, a tractortrailer, a class 5 truck (weighing 16,001-19,500 lbs., two-axle,six-tire single unit), a class 6 truck (weighing 19,501-26,000 lbs.,three-axle single unit), a class 7 truck (weighing 26,001-33,000 lbs.,four or more axle single unit), a class 8 truck (weighing 33,000 lbs.and over, four or less axle single trailer), a vehicle with a GVWRweighing over 14,000 pounds, a vehicle with a cargo to driver mass ratioof 15:1 or greater, a vehicle with six or more tires, a vehicle withthree or more axles, or any other type of high occupancy or heavy-dutyvehicle. In some embodiments, a charging station may charge any otherelectric vehicle, including passenger vehicles. Any discussion herein ofelectric vehicles or electrically powered vehicles may refer to any typeof vehicle discussed and vice versa.

System

An example of automatic docking and charging of a battery electricvehicle involves an urban bus operating on a fixed, cyclical route. Thebus may have on-board batteries to store enough energy to make one ormore complete cycles of its assigned mute, or legs of its assignedroute. One or more of the stops on the route may be at a batterycharging station. While the driver takes his normal break the vehicle isautomatically docked and the batteries charged for the next route cycle.A charging station may or may not be integrated with a passenger stop.Upon final vehicle positioning relative to the charger (vehicle docked),the doors may be opened and passengers are allowed to enter and exit.The control system may be provided such that little to no additionaldriver interaction, beyond typical bus driving skills, is required todock and charge the vehicle. Preferably, each step or many of the stepsof the process may be automatic and error tolerant.

This process may result in a system suitable for placement at a typicaltransit central station without the need for a special, battery electricbus charging station only bus stop.

In some embodiments of the invention, the charging station can comprisea charging connection, such as a charging chassis or overhang, suspendedfrom a charging mount for establishing an electrical connection betweenthe charging station and the electrically powered vehicle. A chargingconnection may have any configuration, which may include a charging armor base that may be provided from a side or base of a charging station.The charging connection may have any orientation, which may include adownward hanging orientation, an upward extending orientation, ahorizontal extending orientation, an angled orientation, or anycombination thereof. The charging connection can comprise a positioningdevice for controlling the position or orientation of the chargingconnection. A power source may be provided to or at the chargingstation. In some instances, the power source may be a grid utility,battery, capacitor, ultracapacitor, fuel cell, generator, renewableenergy source (e.g., solar, wind, hydrodynamic, geothermal, etc.), orany other power source. The power source may be in electricalcommunication with the charging connection.

Another aspect of the invention provides for an electric vehiclecomprising contact plates for establishing an electrical connection to acharging station. The contact plates can be positioned on a top surfaceof the electric vehicle and be positioned in a direction that isrelatively parallel to a direction of vehicle movement. For example, thecontact plates may be spaced apart on the top surface of the electricvehicle. Alternatively, the contact plates may be provided on a side ofthe vehicle, or under the vehicle, or anywhere along a surface of thevehicle. The contact plates may be exposed on the surface of a vehicle,or may be provided beneath a cover. The electric vehicle may have one ormore energy storage system (e.g., batteries, capacitors,ultracapacitors, fuel cell, etc.). The one or more energy storagesystems may be in electrical communication with the contact plates.

The methods of the invention include transferring power to a vehicleusing a charging station. Transferring power to the vehicle can comprisepositioning the vehicle under a charging mount of the charging stationand engaging a charging connection, such as a pantograph, catenary arm,charging chassis or frame, or charging overhang to establish anelectrical connection between the charging station and the vehicle.Transferring power may include any form of electrical connection betweena charging connection (which may have any position or orientation) andone or more contact plate (which may be located anywhere on thevehicle). A vehicle may be charged and/or discharged by establishingelectrical communication between a power source and an energy storagesystem of the electric vehicle. For instance, an electrical connectionmay be made between the power source and charging connection, betweenthe charging connection and contact plate, and between the contact plateand energy storage system.

Examples of configurations for the charging station and/or electricvehicles may include aspects, components, features, or steps provided inU.S. patent application Ser. No. 12/496,569 filed Jul. 1, 2009; U.S.Patent Application Ser. No. 61/289,755 filed Dec. 23, 2009; U.S. PatentApplication Ser. No. 61/328,143 (705.101) filed Apr. 26, 2010; U.S. Pat.No. 5,461,298; U.S. Pat. No. 5,821,731; U.S. Patent No. RE 29,994; B.P.Patent Application No. 2014505; EP Patent Application No. 1997668; PCTPublication No. WO 2008/107767; PCT Publication No. WO2009/014543, whichare hereby incorporated by reference in their entirety.

FIG. 1 shows an example of a vehicle approaching a charging station, ina vehicle charging system provided in accordance with an embodiment ofthe invention. A vehicle charging system may include a charging station100 and a vehicle 110 configured to interface with the charging station.

In some embodiments, the charging station 100 may be provided on aportable, semi-portable, or permanent fixed platform. In some instances,the charging station may be movable from one location to another. Insome instances, it may be easily deployed at a location, but generallyremain fixed at that location. It may also be fixedly integrated into apermanent structure. One example may involve a semi-portable trailer orskid mounted fast charge station. A fast charge station may include acharge pole 120 and vehicle connector head 122, a stationary energystorage module 124, one or more signal receiver 126, and one or moresensor 128.

The charging station may include an electrical connector between thestationary energy storage system 124 and a charging interface, which maybe provided on a vehicle connector head 122. The electrical connectormay be formed of a conductive material, such as a metal, such as copper,aluminum, silver, gold, or any combination or alloy thereof in someinstances, non-metallic conductive materials may be used. In someembodiments, the electrical connector may be formed of one or morewires, bars, plates, or any other shape or configuration.

The charging station may include a charge pole 120. In some embodiments,the charge pole may be collapsible. The charge pole may include anoverhanging arm, which may reach over a vehicle when the vehicleinterfaces with the charging station. For example, a catenary arm mayhang down from a protrusion over the vehicle, and extend downward and/orat an angle to the vehicle. Alternatively, the charge pole may protrudefrom a structure, or from a base or ground. The charge pole may enablean electrical connection to be made with the vehicle on the top of thevehicle, on a side of the vehicle, or underneath the vehicle. The chargepole may be collapsible, or be able to be unassembled for easytransport. The charge pole may have an elongated shape, or may have anyother shape. The charge pole may be integral with a structure orseparate from another structure.

The charge pole 120 may be connected to a vehicle connector head 122.The vehicle connector head may provide an electrical interface for thecharging station 100 for electrically connecting with an electricalinterface of the vehicle 110. As previously mentioned, the vehicleconnector head may electrically interface with the vehicle, anywherealong the surface of the vehicle. The vehicle connector head and anyother portion of the charging station may have a configuration that mayelectrically connect to a vehicle energy storage system to enable thecharging and/or discharging of the vehicle energy storage system.

In some examples, a charging interface on the charging station mayinclude a positive electrode and a negative electrode. The positive andnegative electrodes may be electrically isolated and insulated from oneanother. The positive and negative electrodes may each be in electricalcommunication with the stationary energy storage system. One or moreguiding feature may be provided on the charging station, which mayenable the vehicle to drive up to the charging station and interfacewith the charging station. For example, a vehicle may drive beneath anoverhanging catenary arm of a charging station with a fast chargeelectrical interface, and contact the fast charge electrical interfacewith an electrical interface on top of the vehicle. The structure of thecharging station and/or guiding feature may include flexible componentsor features that may accommodate variations in vehicle size, shape, ordirection of travel. The charging station may also include an interfacethat may ensure a solid electrical connection between electricalinterface of the charging station and of the vehicle. For example, oneor more pressure component, which may utilize a feature such as a springor elastic, or an irregular surface, such as brushes, may be used toensure contact between the charging station and the vehicle.

The charging station may include a stationary energy storage system 124.Alternatively, the charging station may be directly connected to anexternal energy source without requiring a stationary energy storagesystem. The stationary energy storage system may include one or morebattery, ultracapacitor, capacitor, fuel cell, or any other way ofstoring energy. In some examples, the stationary energy storage mayinclude one or more electrochemical batteries. The stationary energystorage may include batteries with any battery chemistry known in theart or later developed. Some batteries may include, but are not limitedto, lead-acid (“flooded” and VRLA) batteries, NiCad batteries, nickelmetal hydride batteries, lithium ion batteries, Li-ion polymerbatteries, lithium titanate batteries, zinc-air batteries or molten saltbatteries. The same storage units or cells may be used, or varyingcombinations of energy storage units or cells may be used. The energystorage units may be connected in series, or parallel, or anycombination thereof. In some embodiments, groupings of energy storageunits may be provided in series or in parallel, or any combination.

In some embodiments, a stationary energy storage system may be providedwithin a housing of the charging station. In some embodiments, theenergy storage units may all be provided within a single housing orpack, or may be distributed among multiple housings or packs. Aspreviously mentioned, the stationary energy storage system may beelectrically connected to a fast charging interface 122. In someembodiments, one or more groupings of energy storage units (e.g.,battery cells) may be directly or indirectly connected to the fastcharging interface via one or more electrical connection.

An external energy source may be a utility or grid. In otherembodiments, the external energy source may be an energy generator, suchas any form of electricity generator. The external energy source may ormay not include power sources such as power plants, or renewable energysources such as solar power, wind power, hydropower, biofuel, orgeothermal energy. In some embodiments, the external energy source mayinclude an external energy storage system, which may include batteries,ultmacapacitors, fuel cells, or so fibth.

The external energy source may electrically connect to a stationaryenergy storage system 124. Alternatively, the external energy source maybe electrically connected to a vehicle connector head 122 withoutrequiring a stationary energy storage system.

The charging station may include a controller. The controller may beable to control the rate of charge for the stationary energy storagesystem from the external energy source. The controller may also permitor not permit the stationary energy storage system to be charged. Insome embodiments, the controller may determine whether the stationaryenergy storage system is charged, discharged, or if nothing happens. Insome instances, the controller may be able to detect or receiveinformation relating to the state of charge of the stationary energystorage system. Any control system may be consolidated or distributedover multiple components. Any action taken by the controller or within avehicle charging system may be directed by tangible computer readablemedia, code, instructions, or logic thereof. These may be stored in amemory.

A vehicle charging system may also include a vehicle 110. Any vehiclemay be able to interface with the charging station. The vehicle may bean electric or hybrid electric vehicle. In some embodiments, the vehiclemay be a bus. The vehicle may also be other heavy-duty or high occupancyvehicles, as discussed previously. Any discussion herein relating to avehicle may relate to any type of vehicle, and any discussion relatingto a specific type of vehicle may relate to other types of vehicles.

A vehicle 110 may have a vehicle energy storage system 130. The vehicleenergy storage system may be used as a propulsion power source for thevehicle. The vehicle energy storage system may include batteries. Insome embodiments of the invention, the vehicle may have one or moreadditional power sources, such as a combustion engine or a fuel cell.The vehicle may be an electric battery-powered vehicle or a hybridelectric vehicle, and may be able to use the same basic batteryconfiguration, drive motor, and controller, regardless of whether thevehicle is an all-battery vehicle or a hybrid vehicle.

In one embodiment of the invention, the vehicle energy storage systemmay include lithium titanate batteries. In some implementations, thepropulsion power source may include batteries that are only lithiumtitanate batteries, without requiring any other types of batteries. Thelithium titanate batteries may include any format or composition knownin the art. See, e.g., U.S. Patent Publication No. 2007/0284139, U.S.Patent Publication No. 2005/0132562, U.S. Patent Publication No.2005/0214466, U.S. Pat. No. 6,890,510, U.S. Pat. No. 6,974,566, and U.S.Pat. No. 6,881,393, which are hereby incorporated by reference in theirentirety.

In accordance with another embodiment of the invention, the vehicleenergy storage system may include batteries with any battery chemistryknown in the art or later developed. Such electric or hybrid electricvehicle batteries may include, but are not limited to, lead-acid(“flooded” and VRLA) batteries, NiCad batteries, nickel metal hydridebatteries, lithium ion batteries, Li-ion polymer batteries, zinc-airbatteries or molten salt batteries. In some alternate embodiments, thevehicle energy storage systems may include a combination of lithiumtitanate batteries and other types of batteries or ultra capacitors.

The use of lithium titanate batteries may enable rapid charging of avehicle, and a long battery life. In some embodiments of the invention avehicle energy storage system may be able to charge to a very high stateof charge within minutes. For instance, in a preferable embodiment,vehicle energy storage system may be able to charge to over 95% state ofcharge within ten minutes. In other embodiments of the invention, avehicle energy storage system may be able to charge to over 65% state ofcharge, over 70% state of charge, over 75% state of charge, over 80%state of charge, over 85% state of charge, over 90% state of charge, orover 95% state of charge within ten minutes, or nine minutes, sevenminutes, five minutes, three minutes, or one minute.

In some embodiments, a vehicle, such as a heavy-duty vehicle, may travela predetermined route, and stop at predetermined points for recharging.See, e.g., U.S. Pat. No. 3,955,657, which is hereby incorporated byreference in its entirety.

The vehicle 110 may have a vehicle charging interface 132 which may becapable of making electrical contact with the charging station 100. Thevehicle charging interface may include a conductive material, which mayinclude any of the conductive materials discussed elsewhere herein. Insome embodiments, the vehicle charging interface may be provided at thetop of the vehicle, while in other embodiments, it may be provided on aside or bottom of the vehicle. The vehicle charging interface may beelectrically connected to a vehicle energy storage system 130. They maybe connected via an electrical connection of the vehicle. The electricalconnector may be formed of a conductive material. In some embodiments,the vehicle charging interface may include a positive and negativeelectrode. In some embodiments, the electrical connection may includeseparate electrical connectors for the positive and negative electrodesto the vehicle energy storage system. The positive and negativeelectrodes may be electrically insulated and/or isolated from oneanother.

The vehicle 110 may include one or more signal emitter 134. The signalemitter may provide a signal from the vehicle to a signal receiver 126at the charging station 100. Any type of signal may be provided from thevehicle to the charging station. In some instances, a unidirectionalsignal may be provided from the vehicle to the charging station.Alternatively, a signal may be provided from the charging station to thevehicle, and/or a two-way communication may be established between thevehicle and charging station. Thus, a signal emitter 134 and a signalreceiver 126 may be able to both emit and receive signals. Preferably,the signal may be transmitted wirelessly between the vehicle andcharging station. Examples of wireless signals may include, but are notlimited to, radio-frequency (e.g., RFID) signals, bluetooth,control-area-network (CAN) messages, or any other form of communication.A signal between the vehicle and charging station may be received whenthe vehicle and charging station are within some proximity to oneanother. For example, the signal may be received when they are about ½mile, mile, ⅛ mile, 100 meters, 50 meters, 40 meters, 30 meters, 25meter, 20 meters, 15 meters, 10 meters, 5 meters, 3 meters, or 1 meterof one another.

The signal may include information about the vehicle's location orposition relative to the charging station, the vehicle's orientation,the vehicle's identification, the state of charge of a vehicle energystorage system, or any other information.

An aspect of the invention may provide automatic detection of thevehicle as it nears charging station and recognition of which vehicle isentering which particular charging station. In some embodiments, thedetection of the vehicle as it nears and/or the identification of thevehicle may be provided via one or more signal that may be exchangedbetween the vehicle and the charging station. In some embodiments, suchidentification may be provided using RFID.

An RFID reader may read a tag located on incoming bus at it enterscharger station. The RFID reader may be a signal receiver on a chargingstation, and the tag may be a signal emitter on a vehicle. The read tagID may be communicated to the charge station controller by means ofdigital outputs activated as a binary number (example: bus tag ID 4 isoutput as 0100). This binary number may be interpreted by the chargestation controller and broadcast over CAN. This eliminates the need tohave an additional computer system to interpret the output of the RFIDreader.

In some embodiments, each vehicle may have a unique tag ID. This mayallow the charging station to identify and/or track specific vehicles.For example, each bus in a fleet of buses may have a unique tag ID. Thetag ID may or may not be provided in binary. Alternatively, one or morevehicles may have the same tag ID. In some embodiments, the tag ID maydenote a group of vehicles, or category of vehicles. For example, allbuses having a particular configuration may have a particular tag ID,while another set of vehicles with different characteristics may haveanother tag ID. The tag ID may be provided with sufficient specificityto determine how a charging station may react to the vehicle. Forexample, a first vehicle category may have a first set of dimensionsthat may require the charging station to accommodate the first set ofdimensions, while a second vehicle category may have a second set ofdimensions that may require the charging station to assume a differentconfiguration to accommodate the second set of dimensions. In someembodiments, a plurality of tag IDs may be provided (e.g., a tag ID fora specific vehicle and a tag ID for a type of vehicle).

A controller area network (CAN) communication between the vehicle andthe charge station may be provided via a wireless communication link(e.g., Bluetooth link). If the approaching vehicle is detected to be anon-battery electric vehicle, no action may automatically be taken. Forexample, if a vehicle is not meant to be charged at the chargingstation, the vehicle may be permitted to pass through or pass by thecharging station without engaging with the charging station. In anotherexample, if the vehicle is configured to be able to interface with thecharging station, but it is detected that charging is not desired atthat point in time, the vehicle may be permitted to pass through or passby the charging station without engaging the charging station.

If the approaching vehicle is detected to be a vehicle that mayinterface with the charging station, and/or to be at a state of chargewhere it may be desirable to charge the vehicle, the charging station,then charging procedures may be initiated. In some embodiments, eachvehicle may recognize its own broadcast ID (e.g., from RFID ID CANmessage sent from charge station) upon entering a particular chargestation and may automatically begin to transmit proper response CANmessages required for docking and charging at that particular chargerstation. The incoming vehicle may begin communicating with a specificcharger upon seeing its ID broadcast by the charging station.

In some embodiments, a charging station may have one chargingconnection. Alternatively, a charging station may have a plurality ofcharging connections. When a plurality of charging stations areprovided, a vehicle may be directed to the appropriate chargingconnection by seeing its ID broadcast at the charging station near thecorrect charging connection.

As a vehicle approaches the charging station, there may be some gentlespeed limiting of vehicle in preparation bor automatically stopping inthe proper location to mate with the charger.

Precise calculation of vehicle position with respect to charger dockingposition may be provided through the use of time/distance integrationusing very accurate measurement of drive axle rotation. For example,fractional (e.g., resolution of 1/64, 1/32, 1/16, ⅛, ¼, ½ of arevolution) measurement of motor revolution×known distance perrevolution=precise distance traveled. This may be combined with feedbackfrom the charger about when the vehicle passes a certain point (from asensor 128 on the charge station) thus yielding position with respect tothe charger. Any other technique may be provided to provide or calculatea relative position between the vehicle and the charger. Various sensorsmay be provided in proximity to the charger, which may include but arenot limited to, weight sensors, light sensors, motion sensors,temperature sensors, magnetic field sensors, gravity sensors, vibrationsensors, pressure sensors, electrical field sensors, sound sensors, orsensors that may detect other physical aspects.

In some implementations, vehicle position verification using topographic“mapping” of the top of the vehicle may be provided. Similarly, vehicleposition verification or mapping of the vehicle may be provided from thebottom of the vehicle, side of the vehicle, or along any orientation ofthe vehicle. Vertical distance to specific, known features on the roofof the vehicle may be measured using a linear distance sensor mountedabove, below, or on the side of the vehicle. Measurements may be matchedto known dimensions on the roof to ensure accurate location of vehicle,both fore-aft and left-right. This feature may ensure the docking arm isbrought down in the correct location to mate with the vehicle. Inaddition, this feature may allow the rejection of other, non batteryelectric vehicles.

Automatic stoppage of vehicle in proper location to dock with chargermay be provided. In some embodiments, the automatic stopping may occurvia application of on-board regenerative braking. For example, a signalmay be provided from the charging station to the vehicle in order toinstruct the vehicle to engage the brakes. The signal may be provided toa vehicle controller which may provide signals to driving mechanisms ofthe vehicle (e.g., brakes, motor, steering). In some instances, theremay be automatically controlled forward movement of vehicle to fullyseat the charger. Similarly, signals may be provided between thecharging station and the vehicle to inform the vehicle to move forwardin a particular manner. The signal may cause a motor speed to becontrolled, and thereby a vehicle speed to be controlled. For example,the signal may inform a motor to slow down, thereby causing the vehicleto slow down.

In some embodiments, such controls may be similar to automatic dockingof the vehicle with the charger. The driving controls of the vehicle maybe engaged based on signals between the vehicle and charging station,and the direction and/or speed of the vehicle may be controlled to bringthe vehicle to a desired position and/or orientation. Such controlsignal may originate from a charging station controller and/or vehiclecontroller. In some embodiments, a driver may or may not be able tomanually override the vehicle control. In some embodiments, normaloperation of brake and accelerator pedals is retained so that driver canstop or drive away at any time if required in the event of an emergency.In some embodiments, components or features of the charging station maymove to assist with the engagement between the vehicle and the charger.For example, a driver may bring a vehicle roughly to a desired location,and one or more features of the charging station may be adjusted toaccommodate the vehicle.

CAN message arbitration may allow multiple vehicles to use the samecharge station at the same time. For example, if multiple signals areprovided between multiple vehicles and the same charge station, the CANmay be able to track which signals are applicable to which vehicles. Insome embodiments, the tag ID of each vehicle may be provided with eachof the emitted signals, so relayed instructions may be tracked to theproper vehicle.

Drivers LCD screen displays information about docking procedure and isused to give any required instructions or communicate faults.

In some embodiments, one or more charge station control system inputsmay be provided. Such inputs may be provided from the vehicle, or fromthe charging station. Some examples of inputs that may be provided mayinclude, but are not limited to, charge arm up position, charge arm downposition, current passing brushes position, neutral brush position,charge head landed on vehicle position, charge head over-temperature,individual (10) brush currents, air supply pressure, RFID Tag ID fromRFID reader, ultrasonic linear distance measurement, CAN messages frombus (e.g., bus readiness for charge status, charge arm commands, batterycharging requirements), or CAN message from chargers (e.g., chargerreadiness status, instant charge voltage, current and power, cumulativeenergy delivered).

Accordingly, one or more charge station control system outputs may beprovided. Such outputs may include, but are not limited to, charge armdown solenoid, charge arm up solenoid, extend current passing brushessolenoid, extend neutral brush solenoid, or CAN messages (e.g., RFID BusID, position of arm status, position of brushes status, ultrasonicmeasurement, charge station readiness status).

In some embodiments, the following automatic charge station dockingcontrol system features may be provided. For example, a dockingprocedure may be tolerant of driver stopping too early (prior to autostop) or being out of position (left-right) and may instruct driver toreposition or try again. In some embodiments, a driver can stop or exitfrom docking procedure at any time simply by releasing parking brake ordriving away.

A CAN system status message can terminate process in the event of afailure after a period of time by sending error message to chargers andbus. The period of time may have any value include, but not limited to,1 ms, 5 ms, 10 ms, 50 ms, 100 ms, 150 ms, 200 ms, 250 ms, 300 ms, 350ms, 400 ms, 450 ms, 500 ms, 600 ms, 750 ms, 1 second, 1.5 seconds, 2seconds, 3 seconds, 5 seconds, 10 seconds, 30 seconds, or 1 minute.

The vehicle charging system may include any of the components, features,characteristics, or incorporate any of the steps involved with avehicle, such as one described in U.S. Patent Publication No.2010/0025132, which is hereby incorporated by reference in its entirety.

FIG. 2 shows an example of a vehicle 200 engaged with a charging station210. For example, the vehicle may be beneath an overhanging arm 220 ofthe charging station. A charging head 224 may be connected to theoverhanging arm via an arm connection assembly 222. In some embodiments,the arm connection assembly may be hanging downward and/or at an angle.The charging head may contact a vehicle charging interface 230 on thevehicle. In some embodiments, the vehicle charging interface may includeone or more guides that may assist with guiding the charging head to adesired location of the vehicle charging interface.

The vehicle charging interface 230 may electrically contact a charginghead 224. This may enable an energy source from the charging station tobe electrically connected to the vehicle energy storage system. They maybe electrically connected via a fast charging interface. The fastcharging interface may enable control over the rate of charge and/ordischarge of the vehicle energy storage system by the stationary energystorage system. In some embodiments, a controller may be provided on thecharging station or on the vehicle that may control the rate of chargeand/or discharge of the vehicle energy storage system. The controllermay also permit or not permit charging of the vehicle energy storagesystem. In some embodiments, the controller may determine whether thevehicle energy storage system is charged, discharged, or if nothinghappens.

As previously described, a vehicle may approach a charging station andcome into contact with the charging station to establish a chargeelectrical interface. When the vehicle comes into contact with thecharging station, an energy storage system on the vehicle may be chargedby a stationary energy storage system of the charging station, anexternal energy source, or any energy source upstream of the fast chargeelectrical interface. A stationary energy storage system may beelectrically connected to an external energy source via a slow charger.

In some embodiments, multiple stationary energy storage systems may beprovided. These stationary energy storage systems may be provided inseries, in parallel, or in any combination thereof. Each of thestationary energy storage systems may be charged and/or discharged atthe same rate or at different rates. In some embodiments, eachstationary energy storage system may be discharged at a faster rate thanit is charged.

In accordance with an implementation of the invention, a vehicle maymake a mechanical connection (pilot) to the charger head to enablecharging. If this mechanical connection is lost, charging can stop aftera period of time. In some embodiments, the period of time may have apredetermined value. For example, the period of time may be 1 ms, 3 ms,5 ms, 10 ms, 15 ms, 20 ms, 25 ms, 30 ms, 35 ms, 40 ms, 50 ms, 60 ms, 75ms, 100 ms, 150 ms, 200 ms, 300 ms, 500 ms, 750 ms, 1 second, 2 seconds,or 5 seconds. Loss of air pressure (used to actuate charge head arm andcurrent passing brushes) or detection of any vehicle movement whilestill docked may interrupt this pilot signal to stop charging in theshortest time possible. Any other fault or error detection may cause thecharging to stop.

While a vehicle is charging, one or more brushes that may be provided ina charging head 224 may contact a vehicle charging interface 230. Anyother electrical connection may be established. When an error or faultis detected, the charging may be stopped to eliminate or reduce thechance of current brushes retracting off the vehicle blade while currentis still flowing.

In some embodiments, a vehicle may dock with a charging station after aset of predetermined criteria have been met Some examples of conditionsthat may be required to allow docking may include: (1) charge head armup (detected home position sensor), (2) air pressure ok (pressuretransducer), (3) charging brushes retracted (position sensor), and (4)charger status ok (CAN message from charger).

Some implementations may include automatic battery charging processcontrol system features. For example, communication, via wireless CAN toa charger, of a vehicle battery state-of-charge may be provided. In someembodiments a requested charging voltage and/or current may be provided.Brush current sensors may monitor individual brush currents and chargingcurrent can be altered (up or down) to maintain highest possible chargerate without forcing too much current through the brushes. The currentmay be monitored to provide any desired current for a condition. One ormore sensor may also determine a brush position (e.g., whether a brushis extended or retracted).

In some embodiments, a total required charge (kWh) may be tailored basedon historical knowledge of energy consumption of vehicle. Historicalusage, predicted future requirements, and knowledge of electricalcharges and rate schedules may be considered and used to adjust bothcharge rate and vehicle charging frequency in order to minimize orreduce electrical demand charges and make the most efficient use ofon-board energy storage. For example, if the next predicted charge ofthe vehicle is predicted to occur in a short interval and the batterystate of charge is sufficiently high, it may be desirable to provideonly minimal charging to the vehicle. In another example, if the nextcharge is predicted to occur after a long interval, it may be desirableto charge the vehicle more.

In some embodiments, before or during charging, a sensor may provide oneor more signal to a charging controller. In some instances, the sensormay provide information about one or more error or alert state. Forparticular error or alert states, the system may react. For example, thesystem may react by stopping the process and/or altering a parameter ofthe process. For example, a temperature sensor may determine thetemperature within a charging head. Over-temperature in the charginghead may immediately stop charging process.

FIG. 3 shows an example of a charging connection of a charging station.Any other types of charging connection may be used. A chargingconnection may include one or more brush 300. A brush may provideelectrical contact between the charging connection and a vehiclecharging interface. A brush may be formed of an electrically conductivematerial, such as a metal, or any other conductive material discussedelsewhere herein. A brush may have any form or shape, which may includebristles, a bar, a plate, one or more protrusions, one or more grooves,or even and/or uneven surfaces.

A brush may have a first position and a second position. In someembodiments, the first position may be a retracted state and the secondposition may be an extended state. In some embodiments, a brush in thefirst position may not make electrical contact with the vehicle, and thebrush in the second position may make electrical contact with thevehicle. For example, a brush in a retracted state may not be inelectrical communication with a vehicle energy storage system.Similarly, a brush in an extended state may be in electricalcommunication with the vehicle energy storage system.

When a vehicle arrives at a charging station and is determined tocorrectly positioned, the brushes may be extended to contact a charginginterface of the vehicle. When charging is complete and/or an error isdetected, the brushes may be retracted and no longer contact thecharging interface of the vehicle. As discussed previously, othercharging configurations or interfaces may be used. Other chargingconfigurations or interfaces may provide a first and second position fora part of a charging interface that may establish and break anelectrical connection, respectively.

A brush may be extended automatically when the vehicle is determined tobe in a desired position. A brush may also be extended in response to asignal or request to extend the brushes. Such a request may be made by adriver of the vehicle, or an operator of a charging station. Similarly,a brush may retract automatically when charging is complete or an errorstate is detected. A brush may also be retracted in response to a signalor request, which may be made by a driver or operator.

Method

FIG. 4 provides a high level depiction of an automated charging methodin accordance with an embodiment of the invention. An automated chargingmethod may include vehicle arrival detection, vehicle positioning, andvehicle charging.

Vehicle arrival detection may identify that a vehicle is approaching acharging station. In some embodiments, the arrival detection may alsoidentify the specific vehicle approaching or the type of vehicleapproaching. Vehicle arrival detection may also be able to determine thelocation or the vehicle and/or the position of the vehicle with respectto the charging station. Other parameters associated with the vehicle,such as the speed and/or direction of the vehicle may be determined.Such vehicle arrival detection may be automatic as the vehicle enters apredetermined proximity of the charging station. The detection may beprovided when a signal emitted from the vehicle is received by thecharging station.

Vehicle positioning may include automated positioning of the vehicle. Insome embodiments, as a vehicle approaching the charging station, thecharging station may use information gathered during vehicle arrivaldetection to control the vehicle drive controls to bring the vehicleinto a desired position. For example, the charging station may controlthe steering, acceleration and/or deceleration of the vehicle. Inanother example, one or more configuration of the charging station maybe altered to accept the vehicle. A charging connection may be madebetween the vehicle and the charging station.

Vehicle charging may include the actual charging of the vehicle. Therate of charge and/or discharge of a vehicle energy storage system maydepend on information gathered during vehicle arrival detection and/orvehicle positioning. For example, the battery state of charge or anyhistorical/predictive information about the vehicle may be used todetermine whether to charge the vehicle or how much to charge thevehicle. When the desired amount of charging is complete, the vehiclemay be disconnected.

FIG. 5 provides a depiction of an automated charging method inaccordance with an embodiment of the invention. The automated chargingmethod may include the steps of identifying a vehicle arrival, locatingthe vehicle, connecting the charging arm with the vehicle, automaticallypositioning the vehicle, charging the vehicle, and procedures whencharging is complete. In some instances, vehicle arrival detection mayinclude identifying the vehicle arrival and locating the vehicle.Vehicle positioning may include connecting a charging arm with a vehicleand automated vehicle positioning. Vehicle charging may include chargingthe vehicle and undergoing procedures when charge is complete.

During vehicle arrival identification, the vehicle may approach thecharging station. Signals may be exchanged between the charging stationand the vehicle, thus allowing communications between the two. A drivermay drive the vehicle to an approximate desired location. In someembodiments, one or more guides may be provided that may assist withdirecting the driver to the desired location. The vehicle may beidentified. In some embodiments, the specific vehicle may be identified.Alternatively, the vehicle type may be identified. The vehicle positionmay be automatically controlled. For example, the speed of the vehiclemay be reduced. In some instances, the direction of the bus may also becontrolled. The station may determine whether the vehicle is meant tointerface with the charging station. If the vehicle is not meant tointerface with the charging station (e.g., if the vehicle is not anelectric vehicle, or if the vehicle state of charge is sufficient),nothing may occur and the vehicle may pass through or pass by thecharging station. If the vehicle is meant to interface with the chargingstation, the vehicle location may be determined.

Locating the vehicle may involve receiving one or more signal todetermine the position of the vehicle relative to the charging station.For example, one or more ultrasonic sensor may be used to detect whenthe vehicle passes a particular position. The sensor may be able todetect a locating feature of the vehicle. In some embodiments, acontroller may determine whether a locating feature was sensed within anappropriate amount of time. If not, the bus may be determined to be outof position and a driver may try to reposition the bus. If the featureis detected within a desired amount of time, the bus may be determinedto be in a desired position, and the bus may be automatically stopped.

Connecting the charge arm to the vehicle may occur as the bus is withina desired location relative to the charge station. For example, if acharge arm is overhanging the vehicle, the charge arm may be loweredonto a roof guide of the vehicle. The roof guide may have some tolerancethat may enable the charge arm to contact the roof guide even if the busis not at a very precise position. A controller may determine whetherthe charge arm is down. If the charge arm is not down, an error may haveoccurred, and the process may be stopped. If the charge arm is down, theprocedure may continue.

Automated vehicle positioning may occur after a charger is connected tothe vehicle. The vehicle may automatically be put into a desiredlocation. For example, a vehicle may be automated moved a particularamount within a desired speed limit. The vehicle may be automaticallystopped when it is at a desired location. In some instances, the vehiclebrakes may automatically be engaged. A controller of the system maydetermine whether the bus is at the desired location and that the brakeis set. If not, then the controller may determine that an error hasoccurred. If no error is detected, and the vehicle is a passengervehicle, such as a bus, the movement of the vehicle may be locked andpassengers may be allowed off.

Vehicle charging may occur after a vehicle is at a desired position anda connection is established between the charging arm and the vehicle.The charging arm may include one or more brushes, and may extend suchbrushes to form an electrical contact with the bus. A controller maydetermine whether the brushes have been extended. If the brushes are notextended, an error may be detected. If only some of the brushes areextended, the procedure may or may not continue. Once the brushes areextended, current flow may begin. One or more sensors may be providedwhich may check whether the current and temperature are within a desiredrange. If not, an error may be detected and the charging connection maybe broken. If they are within the desired range, charging may continueuntil complete.

Once charging is complete, one or more steps may be provided. Forexample, the system may log charge metrics and release the brushes. Acontroller may determine whether brushes have been successfullyreleased. If they have not, then an error may be detected and theconnection between the vehicle and charging station may be broken. If noerror is detected, the charge arm may be released and disconnected fromthe vehicle. For example, a charge arm may be lifted. The controller maydetect whether the arm has been successfully lifted. If it has, chargingmay be complete, and the vehicle may be unlocked (e.g., a brake may bereleased). The driver may drive the vehicle away when ready.

FIG. 6A-F provides a block diagram for a docking and charging procedureas provided in an embodiment of the invention. FIG. 7A-G provides atable describing the steps for an automatic docking and chargingprocedure. The features described in the block diagram and table may beused in combination or separately. The diagrams and table provideexamples of steps for a docking and charging procedure in accordancewith an embodiment of the invention, and any steps described therein maybe optional, in a different order, may be exchanged with similar steps,or may have additional steps added thereto.

FIGS. 6A and 7A provide an example of steps involved in identifying avehicle arrival. In one example, the vehicle may be a bus, although anydescription herein may also apply to any other type of vehicle. A busmay near a charging station, as provided in step A. In some embodiments,a bus may be near a charging station at a predetermined distance fromthe charging station. The predetermined distance may be fixed or mayvary based on circumstance. In some instances, the predetermineddistance may be about 3000 feet or less, 2000 feet or less, 1500 feet orless, 1000 feet or less, 750 feet or less, 500 feet or less, 300 feet orless, 250 feet or less, 200 feet or less, 150 feet or less, 100 feet orless, 50 feet or less, or 10 feet or less. A vehicle controller on thebus may look for one or more signals (e.g., CAN messages fromBluetooth). The charging station may be waiting for a signal from thebus. For example, the charging station may be waiting for CAN messagesfrom the bus. The charging station may perform periodic air pressuretests.

As indicated in step B, signals may be exchanged between the bus and thecharging station. For example, Bluetooth CAN may automatically begincommunication with the bus. In some embodiments, one bus can be providedper CAN network. Alternatively, multiple buses may communicate over aCAN network, or other network. This may be desirable in situations wherea charging station can accommodate multiple vehicles.

When a bus receives a signal, it may start a main routine (e.g., uponreceipt of a charging station CAN message). This may set a chargerreadiness flag on the bus, upon receiving a good communication from thecharging station. In some embodiments, a display may be provided, eitherat the charging station, or within the bus. The display may indicatewhich charge station to go to, or a status of the station (e.g.,charging readiness). The display may also indicate to the driver thespeed of the bus (e.g., mph). In some embodiments, a vehicle controlsystem may apply a filter to the charge station CAN messages based onthe side of the charger. This may be done using RFID. The display mayindicate whether a connection has been made. Preferably, such anindication may be provided as soon as possible. A driver may be trainedto stop by themselves if no connection signal is made.

Meanwhile, the charging station may be checking for air pressure, andmay check on the status of the charger. For example, the chargingstation may check for an ok from the charger. It may then send an ok toa charge flag. The charging station may also check on the status fromRFID. The charging station may also determine that the charging armposition is up, and check so that any subsequent ultrasonic sensorreadings may be accurate.

Step C indicates that a driver may drive the bus to an approximatedesired position. One or more guides may be provided to assist thedriver with positioning. For example, a line may be provided on thepavement for left/right placement Additional types of guides may beused. For example, bars, flags, hanging lines, or other guides may beprovided.

In some instances, no control information may be provided for initialleft/right placement of the bus. Alternatively, a display may indicatewhether the driver should move more toward the left or right. Thedisplay may also indicate to the driver to slow down if the driver isgoing too fast. If the driver moves too fast, the bus may not becharged.

A bus may be identified as indicated in step D. In some instances, RFIDmay be used to identify the bus, although any other signal may be used.The bus may be identified at a distance from the charging arm. In someembodiments, the distance may be about 100 feet or less, 50 feet or less30 feet or less, 10 feet or less, 8 feet or less, 5 feet or less, 3 feetor less, 1 foot or less from the charging arm. An RFID tag on the busmay result in the transmission of a bus ID CAN message. Upon receipt ofthat ID CAN message the bus may automatically ramp its speed to adesired speed. One example of a desired speed may be about 15 mph orless, 10 mph or less, 8 mph or less, 5 mph or less, 3 mph or less, 2 mphor less, or 1 mph or less. In some embodiments, accommodations may bemade to balance variations in distance of detection. Such variations mayoccur due to weather or other conditions. In some instances, the speedramping may be affected based on variations in detection distance.

As indicated in step E, a controller may determine whether the bus is abus that is intended to interface with the charging station. This maydepend on the specific bus ID, or the type of the vehicle. This may ormay not take into account the state of charge of the bus and/or anyhistoric/predictive information. If the bus is not meant to interfacewith the charging station, no steps may be taken. Alternatively, stepsnot leading to charging the vehicle may be taken.

The bus controls may monitor driver speed and disallow docking if thespeed is too high. The bus speed may be provided on a display, whetheror not auto control has taken place. A CAN message may be providedindicating whether RFID has detected the bus. A bus controller mayensure that the bus is in first gear, or operating at a desired speed.Upon receipt of the RFID CAN message, vehicle speed limiting may occur.For example, a vehicle speed may be ramped to 3 mph or less, or 2 mph orless, or any other speed discussed elsewhere. The bus controls may waitfor a signal from an ultrasonic sensor. In some instances, charging maybe disallowed if ride-height is not nominal. In some instances, atolerance range may be provided for a bus ride height For example, aheight delta of 2 feet or less, 1 feet or less, 6 inches or less, 4inches or less, 3 inches or less, 2 inches or less, 1 inch or less maybe provided. The display may indicate when a bus is at a desiredposition, and the bus may be stopped.

The charging station control may communicate with the bus. In oneexample, RFID may come through the Ethernet, to a CAN gateway, orpotentially from reader outputs. The charging system controls maycommunicate with bus controls. In some instances, control decisions maybe made by the charging station controls, vehicle bus controls, or both.

FIGS. 6B and 7B provide an example of steps involved in locating avehicle. As provided in step F, a sensor may determine if a bus is at adesired position. For example, an ultrasonic sensor may see the front ofa bus pass under a charge arm. Then the sensors may be used to beginmeasuring bus position. In some embodiments, a bus's subsequent positionmay be detected using sensors or may be calculated based on datacollected about the bus at specified points in time. For example, if abus' location, speed, and/or direction is known at a particular time,the bus' subsequent positions may be calculated or estimated. Bus wheelrotation count may assist with determining bus location.

In step G, the system may wait for a sensor to see a locating feature(e.g., expected distance to a known item on a roof). For example, a busmay have a locating feature on a roof or any other part of the bus thatmay be detected by a sensor. In some instances, one or more locatingfeature may be provided at the front of the bus, at the front of a roofguide, at a contact plate, at the rear of a roof guide and/or at a rearof the bus. Locating features may or may not be provided at specificmeasurement ranges. The sensors used to detect a locating feature may beultrasonic, optical, mechanical, electrical, magnetic, thermal, or mayinclude any other types of sensors described elsewhere herein.

A vehicle controller and/or charging station controller may receive aCAN message containing distance measurement information from anultrasonic sensor that indicates that the bus has passed under acharging arm. Distance integration may begin. One or more reset pointsmay be provided, which may correspond to one or more locating feature.In one example, distance integration to a reset point 1 (beginning ofAir Condition unit) may occur. A watchdog time to reset point 1 may bebased on average speed. Reset points may be specific measurements of anultrasonic sensor. The time to reset point 1 may be stored in a registerand checked against bounds. The system may continue integration from thefront of the bus if time to reset point 1 is out of bounds. If the timeis in bounds, integration to point 1 may be reset. The system may thenbegin distance integration to reset point 2 (back of Air Conditionunit). The system may watchdog time to reset point 2 based on averagespeed. The time to reset point 2 may be stored in a register and checkedagainst bounds. The time since initial start of integration may bechecked as a potential back-up. The system may then wait for a finallocation point 3 (e.g., portion of charge arm landing ramp that is lowerby several inches), and time to this point may be carefully bounded. Theleft and right location of the bus relative to the charge arm may beverified by a final location point 3 distance measurement that may onlybe correct if the bus is positioned appropriately both front/rear andleft/right. Any number of reset points (e.g., 1 or more, 2 or more, 3 ormore, 4 or more, 5 or more, 6 or more, 8 or more, 10 or more, etc.) maybe provided at any location of the bus. The various reset positions andtiming may be provided in accordance with an embodiment of theinvention.

The charging station may check for a proper signal from ultrasonicsensors. The signal may preferably be within a window allowing for rideheight differences.

At step H, a controller may determine whether a locating feature wassensed in appropriate time. In one example, the appropriate time may beabout 1 minute or less, 30 seconds, or less, 20 seconds or less, 15seconds or less, 10 seconds or less, 8 seconds or less, 5 seconds, orless, 3 seconds or less, 1 second or less, 500 ms or less, 250 ms orless, 100 ms or less, or 50 ms or less, or any other time framediscussed elsewhere herein. If the locating feature is not sensed, thebus may be out of position, and the driver may be informed to try again.If the locating feature is sensed in the required amount of time, thebus position may be ok.

If a final point measurement and time are both within the desired range,a bus controller may begin a bus stop routine. The doors may be disabledunless a parking brake is set, in case the bus driver stop the bus toosoon. If a bus driver does stop a bus too soon, a display may indicateas such. The display may also inform the driver that to charge the bus,the driver may need to release the brake and pull ahead slowly whensafe. The bus may automatically stop when it is in the correct position.

Step J indicates that when a bus position is within a desired range, thebus may be automatically stopped. A bus controller may ramp the busspeed to zero using regenerative braking. This may be done in as short atime as comfortably possible. The controller may wait for the bus toreach zero speed. Then the bus may be shifted to neutral and a brake maybe engaged. For example, the controller may apply rear door brakeinterlock. A display may indicate that the bus is waiting for the chargearm to lower. The bus may move ahead automatically.

FIGS. 6C and 7C provide an example of steps involved in connecting acharging arm with a vehicle. As provided in step K, a charge arm may belowered onto a bus roof guide. The bus roof guide may have sometolerance build in so that the charge arm may engage with the roof guideeven if the bus is not at a precise location. Sensors may detect whenthe charge arm starts to move, and when it is extended. In someembodiments, the sensors may be able to detect this based on a sensor inan air cylinder of the charge arm. Any other sensors may be used todetermine the position of a charge arm.

A bus or charging station controller may be used to begin anarm-lowering sub-routine. The bus controller may send a signal to thecharging station that the bus is in position. This may cause the arm tobe lowered. The arm movement may be checked. For example, the armmovement may be checked by loss of home position. The system may alsocheck whether the arm cylinder is down and then wait for head downindication (ex. Microswitches). A charging station controller mayactuate an arm down solenoid. Any other type of actuator may be used tocause the arm to move. For example, motors, solenoids, linear actuators,pneumatic actuators, hydraulic actuators, electric actuators,piezoelectric actuators, or magnets may be used. The charging stationmay send the arm moving. The arm may move down.

Step L may check whether the charge arm is down. For example, twoswitches may close when charge arm is on a landing pad. If it landsshort or to the side, both switches may not make contact. If the arm isdetected to not be down, an error CAN message may be provided. This maystop the procedure and a problem may be reported. If the arm ispartially down, the arm may be lifted. A display may indicate to thedriver to call for assistance. Once all switches are good, a buscontroller may begin a final bus movement subroutine.

FIGS. 6D and 7D provide an example of steps involved in automatedvehicle positioning. In step M, a bus drive mechanism may beautomatically controlled to place bus in a desired position. Forexample, the bus may be automatically moved forward at a governed speed.In some instances, the bus may be moved forward about 20 feet, 15 feet,12 feet, 10 feet, 7 feet, 4 feet, 3 feet, 1 foot, or any other distancedescribed elsewhere herein. In some embodiments, the governed speed maybe about 10 mph or less, 8 mph or less, 5 mph or less, 3 mph or less, 2mph or less, 1 mph or less, or any other speed described elsewhereherein. The bus may move forward automatically, or the driver may beinstructed to move the bus ahead and then it may automatically stop oncea charge head is engaged with the bus. In some embodiments, one or moreswitches may be provided to make contact when a bus is at a desiredlocation.

A bus controller may indicate on a display that the bus will moveforward automatically and then stop to charge. The bus may also informthe driver to release a brake pedal. Alternatively, the brake pedal mayautomatically be released. In some embodiments, a bus controller maycheck that the driver is off the pedal. The bus controller may send amotor torque signal as low as possible to move the bus slowly andsmoothly. This may begin distance integration as soon as the bus movesto use a watchdog. The bus controller may wait for a pilot signal toindicate the charge head is in the correct position.

Step N provides that a bus may be automatically stopped when a pilotsignal and ground are made. This may indicate that the bus is at adesired position. In some instances, a bus controller may automaticallystop the bus once it is in position using the same procedure asdescribed in step J. Alternatively, a different procedure may be used.

Step P may allow the bus to be automatically shifted to neutral and abrake may be automatically engaged. The brake may be a rear door brakeinterlock. Automatic stops may be accomplished by regenerative brakingor by controlling a motor to zero rpm. Once a bus is in final position,a rear door brake interlock may be automatically applied (to prevent thebus from rolling), and the bus may be shifted to neutral. In someinstances, a display may inform a driver to set a parking brake. Thedriver may be instructed to set a parking brake, or the parking brakemay be automatically engaged. Once the desired brakes are engaged, thedoors may be opened and charging may start. If the driver wants to driveaway prior to setting the parking brake, he may step on the brake andshift to drive. This may release the rear door brake interlock. Thedoors may be prevented from opening to discourage this under normalcircumstances. If the parking brake had been set and charging started,releasing the parking brake may be sufficient to stop charging.Releasing the parking brake during charging may be considered anabnormal condition.

A bus controller may apply regenerative braking to reduce the bus speedto zero. The bus controller may also automatically shift thetransmission to neutral. Alternatively, a driver may be instructed toshift the transmission to neutral. The bus controller may apply a rearbrake interlock. A display may indicate to the driver to set a parkingbrake to allow bus doors to open and the bus to charge.

Step Q may allow a controller to check if the bus location is within adesired range, and whether the desired brakes are set. If this conditionis not met, the procedure may be stopped. A problem may be reportedand/or the arm may be lifted. The bus controller may check for a parkingbreak.

In accordance with step R, bus movement may be locked to allowpassengers off. In some embodiments, an acceleration pedal may bedisabled. The system may continuously check for a parking brake. Oncethe bus movement is locked, the doors may be allowed to open, and adisplay may indicate that the bus is charging. A charging stationcontroller may check for a pilot signal from a charger prior to allowingcharging.

FIGS. 6E and 7E provide an example of steps involved in charging avehicle. As indicated in step S, during charging, charge brushes may beextended from a charging arm of a charging station. Position sensors maybe provided at each cylinder to indicate when a cylinder is home (notextended).

A bus controller may begin a charging sub-routine during charging. Itmay send a signal to extend a ground brush. It may wait for confirmationor a signal that a ground brush has been extended. It may send an ACsignal or tone to ensure that the ground is connected. If the ground isconnected, the controller may signal the charge brushes to extend. Thecharging station controller may provide a signal to extend a groundingbrush air cylinder. The charging station controller may also extendcharging brush air cylinders.

Step T verifies whether the brushes are out. If they are not all out,but some brushes are out, the procedure may continue with some of thebrushes not extended. Continued operation may be at a reducedperformance in proportion to number of brushes not extended. If too manyof the brushes are not out, an error may be indicated. A display mayindicate to report the problem. The charging arm may be lifted.

A bus controller may wait for all brushes to extend. In someembodiments, there may be 1 or more, 2 or more, 3 or more, 4 or more, 6or more, 8 or more, 10 or more, 12 or more, 16 or more, 20 or more, 30or more, 40 or more, or 50 or more brushes. The controller may wait forall brushes to extend, or may wait for a predetermined number of brushesto extend.

As provided in step U, current flow may be initiated. In someembodiments, the bus may control the charge process. The bus may send aCAN message to the charging station to begin the charge. Alternatively,the charging station controller may control the charge process. A buscontroller may send a signal to the charging station that it is ok tostart charging. The charger may report time to charge.

A controller may determine whether the charging current or temperaturefalls within a desired range in step V. For example, a desired level ofcharging may be provided based on the bus battery state of charge,and/or historic/predictive factors. A desired charge characteristic(e.g., voltage, current amplitude, pulsing, duration, etc.) may have apredetermined range. Similarly, a temperature may have a predeterminedrange. The current and temperature may be monitored periodically orcontinuously. If they fall outside the desired ranges, a problem may bereported. The charging arm may be released and/or lifted.

Step W may be to wait for the charge to complete. The charge may beapplied for a predetermined amount of time. Alternatively, a vehiclestate of charge may be monitored, and the charge may occur until thevehicle battery has reached a desired state of charge. In someinstances, a display may indicate that the status is charging. Thedisplay may also indicate the time left to complete charging or thepercent charging that has been completed. Any other status updated maybe provided on a display while the bus is charging. A bus controller maystop current flow if there is a loss of pilot, over temperatureindication, based on a report back from a battery management system, ora report back from a charger. A charging station may continuouslymonitor temperature switches. The charging station may also closedistribution box contactors.

In step X, the system may determine when charge is complete, or that adesired state of charge has been obtained. In some embodiments, thedesired state of charge may be when a vehicle battery has been fullycharged. Alternatively, the desired state of charge may be any valuebased on historic/predictive data for the vehicle. If the charge is notcomplete after a predetermined amount of time, an error may be reported.The charging arm may be released and/or lifted. A display may indicateto call for assistance.

FIGS. 6F and 7F provide an example of steps involved when charging iscomplete. In step Y, charge metrics may be logged. For example, theinitial battery state of charge, the charging parameters (e.g., voltage,current amplitude, duration of charging, total power, faults, time, peakcurrent, etc.), battery end state of charge, may be logged. In someinstances, the bus controller may be logging the charge metrics when thecharge is complete. In some instances, the charge metrics may berecorded during charge. The charge metrics may be recorded on a bus datarecorder. In some embodiments, they may be recorded only for the timebeing. Alternatively, they may be recorded for an extended amount oftime. In some instances, the data may be manually retrieved.Alternatively, the data may be accessible and may be automaticallyretrieved.

In step Z, a controller may determine whether brushes have beenreleased. If the brushes have not been released the procedure may bestopped. A problem may be reported. If possible, the charging arm may bereleased and/or lifted. A display may be provided to call forassistance.

A bus controller may begin a charge done sub-routine. Charging may bestopped, and a signal may be provided to release brushes. The controllermay wait for all brushes to be released and returned to a retracted(e.g., home) position. A signal may be provided to release ground. Insome instances, the controller may wait for the ground to get home.Confirmation may be made that the brushes and ground have been returnedto a home position. A signal may be provided to raise the charge arm.

In response to a signal from the bus controller, the charge station mayraise the charging arm. In some instances, the charge station controllermay ensure that the arm has returned to a home position for the nexttime.

In accordance with step AA, the charge arm may be lifted. A buscontroller may wait for a loss of head micro switches (charge head notdown) before allowing a driver to move.

In step BB, the charge arm position may be verified. For example, basedon air cylinder position, it may be determined whether a charging arm isup. If not, the procedure may be stopped and/or a problem may bereported. If the arm is successfully up, the bus controller may releasea rear-door brake interlock and allow movement.

As indicated in step CC, when charging is complete the bus may beunlocked. A display may indicate to a driver that the charge iscomplete, and to release a parking brake and select a gear to driveaway. As indicated in step DD, when the bus is charged, the parkingbrake may be released and the driver may select a drive option. Thedriver may proceed when ready. In some instances, a display may indicatea battery state of charge or a fuel gauge. For example, a full fuelgauge may be displayed.

As previously mentioned any of the steps herein may be provided by oneor more controller of the system. One or more bus controller or chargingstation controller may be provided. Any of the functions, which may beindicated to be performed by a bus controller or charging stationcontroller may be performed by any other controller. In someembodiments, tangible computer readable media may be provided to enablethe functions to be carried out. The computer readable media may includelogic, code, instructions to carry out such steps.

FIG. 7G provides an example of steps involved in relation to differentfaults within the system. When a fault is detected, a fault sub-routinemay be run. The charger may be signaled to stop. Brushes may bereleased. The rear-door brake interlock may be released. During a fault,bus movement may be allowed if the driver uses pedals and releases abrake. A signal may be provided to lift the arm up. Any fault code maybe logged. A display may be provided indicating that charging hasstopped and to contact support. The display may include a number ornormal trouble routine.

A display may be provided to a driver and/or operator of a chargingstation. The display may be provided at a charging station or on avehicle. The display may be provided on a display device, such as ascreen. Some examples of display devices may include whether aparticular charging station is ready or not ready (e.g., chargingstation 1 is ready, charging station 2 is not ready, etc.). The displaymay also indicate whether communication has been established. Thedisplay may also include driving instructions (e.g., please drive slowto 5 mph) before the charge station or auto charging may not take place.Alternatively, the system may take control without providing suchinstructions. In some instances, a display may indicate the speed of thevehicle (e.g., x.x mph). The speed may be precise. If the speed isacceptable, charging may take place, and the display may indicate assuch. In some embodiments, the display may indicate that the driverought to be prepared to stop if required. The display may also instructa driver to drive in a manner aligned with a driving guide. In someinstances, if the driver strays too much to the left or right a warningmay be provided. If the bus is moving too quickly, the display mayindicate to the driver to slow down. The display may warn the driverthat the vehicle may not charge if it comes in too quickly.

The display may provide instructions for charging the bus. For example,the display may inform the user that to charge the bus, the brake may bereleased and to pull ahead slowly when safe. The bus may automaticallystop. The display may indicate as a driver approaches the initial stopposition, and the bus may automatically stop, and to release the brakeif safe. The display may also indicate that while waiting for the chargearm to lower, the bus may move ahead automatically to charge, and torelease brake if safe. Once a bus is connected to a charger, the displaymay indicate as such, and instruct the driver to set a parking brake tostart the charge and allow the vehicle doors to open. While the bus ischarging, the display may indicate the battery state of charge or howmuch time left to charge. A fault may be indicated if the bus is notcharged, and to contact maintenance. When charging is complete,instructions may be provided to select drive and release the parkingbrake when ready. If the bus is out of position, the display mayindicate to drive around and try again (e.g., not back up). In someinstances, password access may be granted. A diagnostic screen may beshown indicating battery specifics and fault codes.

It should be understood from the foregoing that, while particularimplementations have been illustrated and described, variousmodifications can be made thereto and are contemplated herein. It isalso not intended that the invention be limited by the specific examplesprovided within the specification. While the invention has beendescribed with reference to the aforementioned specification, thedescriptions and illustrations of the preferable embodiments herein arenot meant to be construed in a limiting sense. Furthermore, it shall beunderstood that all aspects of the invention are not limited to thespecific depictions, configurations or relative proportions set forthherein which depend upon a variety of conditions and variables. Variousmodifications in form and detail of the embodiments of the inventionwill be apparent to a person skilled in the art. It is thereforecontemplated that the invention shall also cover any such modifications,variations and equivalents.

What is claimed is:
 1. A method of charging an electric bus at a charging station, the bus including a charging interface on a roof and the charging station including a charging head configured to engage with the charging interface to charge the bus, comprising: determining that a bus approaching the charging station is supposed to be charged at the charging station; lowering the charging head of the charging station to land on the roof of the bus; moving the bus, with the charge head sliding on the roof of the bus, to engage the charging head with the charging interface; and activating current flow through the charging head to charge the bus.
 2. The method of claim 1, wherein lowering the charging head includes lowering the charging head to land on a region of the roof away from the charging interface.
 3. The method of claim 1, further including raising the charging head from the roof after charging is complete.
 4. The method of claim 1, further including determining a position of the bus relative to the charging station as the bus approaches the charging station.
 5. The method of claim 1, further including receiving identifying information of the bus as the bus approaches the charging station.
 6. The method of claim 1, wherein moving the bus includes stopping the bus when an electrical signal indicates electrical contact between the charging interface and the charging head.
 7. The method of claim 1, wherein lowering the charging head includes detecting whether the charging head has landed in a desired region of the roof and raising the charging head from the roof if the charging head has not landed on the desired region.
 8. The method of claim 1, wherein moving the bus includes moving the bus at a speed controlled by the charging station.
 9. The method of claim 1, wherein lowering the charging head includes lowering the charging head only if it is determined that the approaching bus is supposed to be charged at the charging station.
 10. The method of claim 1, further including locking movement of the bus when current flows from the charging head to the charging interface.
 11. A method of charging an electric bus at a charging station, the bus including a charging interface positioned on a roof and the charging station including a charging head configured to engage with the charging interface to charge the bus, comprising: identifying the bus as the bus approaches the charging station; controlling a speed of the bus from the charging station; lowering the charging head to land on the roof away from the charging interface; moving the bus after the lowering to engage the charging head with the charging interface; stopping the bus when an electrical signal indicative of electrical contact between the charging head and the charging interface is received; and activating current flow through the charging head to charge the bus.
 12. The method of claim 11, wherein lowering the charging head includes detecting whether the charging head has landed in a desired region of the roof and raising the charging head from the roof if the charging head has not landed on the desired region.
 13. The method of claim 11, wherein moving the bus includes sliding the charging head on the roof of the bus towards the charging interface.
 14. The method of claim 11, further including determining that a bus approaching the charging station is supposed to be charged at the charging station prior to controlling the speed of the bus.
 15. The method of claim 14, wherein lowering the charging head includes lowering the charging head only if it is determined that the approaching bus is supposed to be charged at the charging station.
 16. The method of claim 11, further including locking movement of the bus during charging.
 17. A method of charging an electric bus at a charging station, the bus including a charging interface positioned on a roof and the charging station including a charging head configured to engage with the charging interface to charge the bus, comprising: identifying the bus as the bus approaches the charging station; controlling a speed of the bus from the charging station after the identifying; detecting features on the roof of the bus to position the roof below the charging head; lowering the charging head to land on the roof; moving the bus after the lowering such that the charging head slides on the roof towards the charging interface; stopping the bus when an electrical signal indicative of electrical connection between the charging head and the charging interface is received; and charging the bus.
 18. The method of claim 17, wherein lowering the charging head includes detecting whether the charging head has landed in a desired region of the roof and raising the charging head from the roof if the charging head has not landed on the desired region.
 19. The method of claim 17, further including determining that the identified bus is supposed to be charged at the charging station prior to controlling the speed of the bus.
 20. The method of claim 19, wherein lowering the charging head includes lowering the charging head only if it is determined that the identified bus is supposed to be charged at the charging station. 